fix(build): clippy 1.93.0 compliance

clippy 1.93.0 added/tightened several lints that broke `cargo clippy -D warnings`
(the release gate). All behavior-preserving:

- unnecessary_map_or: `signer_parent.map_or(false, |r| …)` → `is_some_and`
  (relicario-server/src/main.rs).
- needless_question_mark: drop redundant `Ok(… ?)` wrappers around
  `serde_json::from_str(…).context(…)` in org_session.rs load_meta/load_members/
  load_collections.
- print_literal: inline the trailing "FLAG" header literal in `org audit`.
- items_after_test_module: move `configure_git_signing` above the
  `seed_helper_tests` module in device.rs so the test module is last.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Pe8qw5KePDqAEBsAxnVQuJ

crates/relicario-cli/src/org_session.rs

@@ -56,12 +56,12 @@ impl UnlockedOrgVault {
     #[allow(dead_code)]
     pub fn load_meta(&self) -> Result<OrgMeta> {
         let s = fs::read_to_string(self.org_meta_path()).context("read org.json")?;
-        Ok(serde_json::from_str(&s).context("parse org.json")?)
+        serde_json::from_str(&s).context("parse org.json")
     }
 
     pub fn load_members(&self) -> Result<OrgMembers> {
         let s = fs::read_to_string(self.members_path()).context("read members.json")?;
-        Ok(serde_json::from_str(&s).context("parse members.json")?)
+        serde_json::from_str(&s).context("parse members.json")
     }
 
     pub fn save_members(&self, members: &OrgMembers) -> Result<()> {
@@ -71,7 +71,7 @@ impl UnlockedOrgVault {
 
     pub fn load_collections(&self) -> Result<OrgCollections> {
         let s = fs::read_to_string(self.collections_path()).context("read collections.json")?;
-        Ok(serde_json::from_str(&s).context("parse collections.json")?)
+        serde_json::from_str(&s).context("parse collections.json")
     }
 
     pub fn save_collections(&self, collections: &OrgCollections) -> Result<()> {